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Triiodothyronine increases serum angiotensin converting enzyme
Hormone and Metabolic Research = Hormon- Und Stoffwechselforschung = Hormones Et Metabolisme
|January 1, 1985
Summary
Elevated thyroid hormone, specifically triiodothyronine, directly increases serum angiotensin converting enzyme levels in hyperthyroidism. This study confirms thyroid hormone, not the thyroid disease itself, is the cause.
Area of Science:
- Endocrinology
- Biochemistry
- Physiology
Background:
- Hyperthyroidism is associated with elevated serum angiotensin converting enzyme (ACE).
- The precise cause of increased serum ACE in hyperthyroidism remains unclear, with potential links to thyroid hormone levels or the thyroid disease itself.
Purpose of the Study:
- To investigate whether elevated thyroid hormone levels are directly responsible for the increased serum angiotensin converting enzyme observed in hyperthyroidism.
Main Methods:
- Administration of varying doses (5-40 micrograms) of 3,5,3'-triiodo-L-thyronine (T3) to female Swiss-Webster mice via oral and subcutaneous routes.
- Measurement of serum, lung, and kidney angiotensin converting enzyme activity in treated mice compared to control groups.
Main Results:
- Significant elevation in serum angiotensin converting enzyme was observed in all mice treated with triiodothyronine.
- Specific activity of lung and kidney enzymes showed moderate reduction, while total activity remained unchanged due to organ size increase.
Conclusions:
- Elevated thyroid hormone (triiodothyronine) per se is the direct cause of increased serum angiotensin converting enzyme in hyperthyroid states.
- The findings differentiate the effect of thyroid hormone from the underlying thyroid disease in altering serum ACE levels.
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